body, div, html, p, h1, h2, h3, h4, h5, h6, span, b, strong, ul, li, img, a, input, button {
 margin: 0;
 padding: 0;
 color: #333;
 font-size: 13px;
 font-family: "微软雅黑 Light";
 box-sizing: border-box;
}

input, button, a, img {
 outline: none;
 background-color: transparent;
 border: none;
}

body {
 background-color: #F5F7FA;
}

ul, li {
 list-style: none;
}

img {
 display: block;
}

a {
 cursor: pointer;
 text-decoration: none;
}

.container {
 min-height: 100vh;
 padding-top: 50px;
 max-width: 768px;
 margin: auto;
 width: 100%;
 display: flex;
 flex-direction: column;
}

.nav {
 display: flex;
 align-items: center;
 position: fixed;
 z-index: 99;
 top: 0;
 left: 0;
 width: 100%;
 height: 50px;
 background-color: #fff;
 padding: 0 20px;
 box-sizing: border-box;
}

.nav img {
 position: absolute;
 left: 20px;
 top: 50%;
 transform: translateY(-50%);
 width: 22px;
}

.nav span {
 color: #333;
 margin: auto;
 font-size: 20px;
}

/**
* pc端时，最大宽度为768px
*/
@media screen and (min-width: 768px){
 .nav {
  display: none;
 }
 .container {
  padding-top: 0;
 }
}
